Induction-alternator.



L. J. LE PONTOIS.

INDUCTION ALTERNATOR.

APPLICATION FILED JAN. 13,1909.

Patented Apr. 8, 1913.

2 BHEETSSHEET 1.

Q L. J. LE PONTOIS.

INDUCTION ALTERNATOR.

APPLICATION FILED JAN.13, 1909.

' v1 5 24 4 v PatentedApr.8, 1913.

my annex do;-

UNITED STATES PATENT OFFICE.

LEON. J. Lu Partners; 0! NEW ROCHELLE, NEW YORK, ASSIGNOR, BY MESNE ASSIGNMENTS, T0 H. w. JOHNS.

mnocrromamnannron.

Specification of Letters Patent.

Patented Apr. 8,1913.

Application filed January 13, 1909. Serial No. 471,997.

duction-Alternators, of which the following is a full, clear, and exact specification.

My invention relates to induction alternators, and although capable of use for various urposes, is particularly well adapt ed for te production of an ignition spark for gas engines.

Among the objects of my invention may be mentioned the production of a generator which will be of high efficiency for the pur- -poses desired, of small size, comparatively well protected from possibility of injury, durable and requiring little or no care or attention.

A further object of my invention is the simplification of the necessaryrontrolhng means usually required in ignition apparatus, particularly the elimination of auxiliary induction coils, my improved generator embodying means for the production of high tension energy forspark ignition in spark plugs of ordinary type in a simpler and more substantial manner than heretofore. I prefer to utilize generators of the magneto type, and in order to secure small size of the field magnets and permanency of maguetization, I provide exciting .coils which serve to maintain the magnetization of the field and also serve as generating coils and moperale with the main generating coil or coils in the production of energy. I

These and other objects of my IHVOllilOll will be understood by those skilled in the art from the following description and accompanying drawings.

Figure 1 is 'a longitudinal sectional view of one form-of machine embodying my invention; Fig. 2 is a sectional. view on the line 2-2 of 1 ig.-1i; Fig. 3 is a diagram of one form of connections; Fig. 4 is a wave diagram; Fig. 5 is alongitudinal sectional view of a modified form of generator embodying my invention; Fig. 6 is a sectional view on the line 6(3 of Fig. 5; and Fig. 7 is a diagram of one form of connections.

Referring to Figs. 1 and 2, the machine is shown as having a field frame made up of two sets of laminte' 1, 2, each set comprising a plurality of stampings having four poles N, S, N, S. The stamping comprising the four polar projections and connecting yokes is preferably made integral, and each stamping is preferably hardened and permanently magnetized separately excepting the polar projections, which remain soft and of high magnetic permeability. I prefer to magnetize and harden the stampings as described in my Patent No. 902,499, granted October 27, 1908. Between t-hetwo sets of assembled laminae 1, 2, extend four connecting portions 3, each made up of laminae of so t iron which are closely fitted in recesses opposite polar projections of the two sets of laminae. At the outer ends of the field frame are rings lwhich, together with tie rods 5, serve to clamp the laminae of the two sets firmly together. The tie rods are each pr0- vided with an enlarged central portion 6 which, with washers 7, serve to space the two sets of laminae at a fixed distance from each other, and the nuts 8 on the tie rods serve to clamp the lamime and end rings firmly together. The field frame is provided with end supports or brackets 9, which are shown held in place by nuts 10 on the tie rods 5, and the end supports are in turn supported by pedestals 11, 11, being journaled therein in order to permit angular adjustment of the field frame with reference to the rotor for the purpose of varying or controlling the time of generation of maximum electromotive force or the time of spark ignition. For the purpose of obtaining this angular adjustment of the field conveniently. one, of the end supports 9 is provided with a projection 12 to which may be connected a lever or other means of control.

\Vithin the end supports is jmunalcd by means of roller bearings the shaft '13 of the rotating element. The latter comprises three portions, a central portion 14. cylindrical in form and of such diameter as will permit en'dwise withdrawal of the rotor through the field frame. an end portion 15 of the form shown in full lines in Fig. 2 and:adapted to vary the paths of the magnetic flux through the pole pieces, and an opposite end portion 16 of the same form as the. part 15, but angularly displaced so as to be at right angles to the portion 15, as shown by dotted lines in Fig. 2. The central portion 14 of the rotor is shown as having radial saw-cuts 17 extending inwardly from the cylindrical surface for the purpose of reducing eddy currents therein. The ro-' tor shaft is shown as having a jaw clutch 18 at one end for the purpose of coupling to the shaft of the gas engine or other driving which, in Fig. 3,-are shown connected in parallel with each other, although o-therconnections of the coils may sometimes be de sirable. Fig. 3 shows the circuit of the windings as being closed through ground connections G- and through a make-andbreak spark device 21. This arrangement of connections is adapted for an ignition system of the make and-break type, the means for operating the breaker 21 of the, engine cylinder and the distributing circuits not being indicated, as the latter form no part of my invention and any suitable means known in the art might be utilized.

With the portions 15, 16 of the rotor arranged at right angles to each .other, the two groups of laminae 1, 2, are so placed that the upper and lower poles in each group are of north polarity and the intervening ones of south polarity. With this arrangement, it will be seen that in the position shown in Figs. 1 and 2, the magnetic flux will have a complete circuit from the two north poles of the left hand portion of the field frame, through the portions 15, 14 and 16 of the rotor to the two south poles of the right hand portion of the field frame, and thence by the connecting parts 3 and yoke portions of the field frame back to the north poles of the left hand portion. The magnetic flux thus passes through the generating coil 20 from left to right. The movement of the rotor will cause the magnetic flux to decrease, and when the rotor has turned 90 degrees, or 180 degrees, electrically, the flux will pass through the generating coil 20 in the opposite direction, the path being from the north poles of the rignt hand portion of the field frame to the portion 16 of the rotor, thence through the portions 14 and 15 to the south poles of the left hand portion of the field frame, and thence through the connecting parts 3 and yoke portions of the field frame back to the north poles at the right. Continued movement of the rotor will cause this change of flux to be repeated, and it will therefore be understood that in one revolution of the rotor, two complete waves of electroinotive force will be generated in the winding 20. Fig.

4 illustrates two complete sine waves, and although of course the waves generated will not be of exactly this form, yet they may serve for the purpose of explanation. The

tromotive force in the oppositedirection and closed again at C, approximately, when the maximum electromotive force in the saine'direction as first considered begins to increase, and then open again at D when the maximum electromotive force, approximately,

5 throughout the period of generation of elec I is'generated, and remains open thereafter throughout the remainder of the cycle considered. It will thus be seen that two sparks per revolution of the gas engine and generator are produced, assuming a pne-to-one who of driving connection. it Wlll be seen that the coils 19 which inclose the field poles will also serve as generating windings due to the change of magnetic flux passing through them, and they will be connected in such relation to each other and to the main generating winding 20 that the electrometi-ve forces generated in each windin will be in the same direction in the circuit the electromotive force generated in the coils 19 substantially correspondingin phase with each other and with that generated in'the main winding 20. Of course the flow of :urrent in one direction through the windings 19 will be such as to tend to strengthen the magnetization of the field, whereas the passage of the current in the opposite direction will tend to de-magnetize the field. I therefore arrange the breaker in such relation to the angular positionof the rotor, or vice verse, that the breaker will be open during the generation of electromotive force in such direction as would tend to demagnetize the field frame if the circuit were closed. By referring to Fig. 4, it will be seen that the circuit is closed during periods of generation of electromotive forces in one direction only, and open during generation of electromotive forces in the opposite direction, and, as above stated, I relate the parts or connections in such manner that the flow of current during the closure of the circuit will cause the strengthening of the field. Also, by the connection of the main generating winding in series with the windings 1!), the latter will be subjected to the current of the main circuit and thereby very appreciably increase the field strength and generation of'energy in the circuit during the utilization thereof by the spark discharge. I thus produce a highly cffieient magneto generator for the purpose described which is very compact, well protected and durable and in which all of the windings and circuit connections are stationary.

In Figs. 5, 6 and 7 I have illustrated a modified form of the generator particularly adapted for high tension ignition. The parts similarly numbered correspond to the parts already described and this description need not be repeated. In place of the main generating winding 20 I arrange two windings of similar form, the inner winding 22 being composed of a comparatively few turns .of coarse wire and the outer winding 23 comwinding 22 through a spark plug 25 and thence to ground, a condenser 26 being connected across the terminals of the breaker 24. The circuit connections to the engine cylinders and the distributer are not indicated in Fig. 7, as the particular means employed for this purpose forms nov part of my present invention. The breaker 36, 31 and means for operating the same is illustrated in Figs. 5 and 6 and comprises a cam 27 of symmetrical form mounted on the.

shaft of the rotor, the cam opera ing to enge a r 28 ivoted on a stu I 2 An arm 30 extends rom the arm 28 substantially at right'angles thereto and carries a, contact 31 which normally forced upward by the leafspring 32 fixed to the bottom of the inclosing case b a screw and nut 33. A

threaded rod 34 ad ustable within the sleeve 35 carries at its lower end a contact 36 cooperating with the contact 31 to form the interrupter. The rod 34 is provided with a check nut 37 and its upper terminal is shown as a ball 38 adapted. to receive a spring clip terminal of the lead from the wlnding 22. The sleeve 35'alnd rod 34 are supported in a block of insulation 39, the latter being securedto the frame support by screws 40 and 41. The latter screw is shown as hollow and with a removable cap for permitting the insertion of oil for lubricating the suppert of arm 28. It will be seen that the arrangement of the parts is symmetrical so that the breaker may be adapted to either direction of rotation of the generator. Thus the arm 28 may be removed from its screw stud and reversed so as to be supported by the screw stud, 42, the screws 40 and 41 may be interchanged, and the leaf spring 32 may be turned about its support so as to occupy a position reverse to that shown. breaker is adapted to be opened twice during each revolution of the generator, and consequently, with a driving connection in the ratio of one-to-one, the proper number for he usual four cylinder engine. The electromotive forces generated in the windings 22 and 19 will cor-respond to those described in connection with Figs. 1 to 4, and the parts are so related that the contacts 31, 36 will engage each other and closethe circuit of the windings 19 and 22 upon themselves during the periods of electromotive force in one direction, as during the periods of A B and C D of Fig. 4. This results in the flow of a comparatively heavy current in the low resistance windings 19 and 22 and the passage of this heavy current tends to maintain the then existing path of the magnetic flux. \Vhen the maximum current is flowing in this closed circuit, the interrupter causes the contacts 31 and 36 to be separated, which removes any tendency to maintain the then existing paths of the magnetic flux, and as the rotor has at such time passed within the influence of adjacent poles and so provided new paths of low reluctance, there will be produced a very sudden change of ;magnetic flux through the windings 22 and '23. There is consequently caused a transfer, .of a considerable amount of energy during Qthis brief period, and the high tension en- ,ergy induced in the winding 23 thus produces a very effective spark discharge, the effectiveness being increased by the action ef the condenser 26.

The breaker will remain open during the generation of the waves in the opposite direction, and closed and opened again during the generation of electroniotive force in the direction first considered, and then remain open during the generation of the wave of opposite direction. By this arrangement the windings The i 19 serve not only as generating windings, but also as exciting windings strengthening the magnetic field, asexplained in connection with Figs. 1 to 4. Another advantage of my improved machine is that the rotatmg element is always balanced, the magnetic. pull on. the opposite faces. of the parts l5, l6, always being substantially the same.

I have found by means of my present in.- vcntion I can produce more efficient spark discharges with a smaller magneto generator than heretofore required and eliminate the auxiliary induction coils in addition.

It will be understood by those skilled in the art that various modifications of the machines above described may be deviscd with- Qdpuble set of laminated permanently magof sparks will be produced per revolution netized multipolar field elements axially displaced, axially extending portions of soft iron connecting said elements, a rotor cooperating with said elements, and a generating winding embracing said rotor.

2. A magneto generator comprising a double set of laminated permanently magnetized multipolar field elements axially displaced, axiallv extending portions of soft iron connecting said elements, a rotor cooperating with said elements, windings on said elements, and a generating winding embracing said rotor, said latter winding and first-named windings being connected in the same circuit.

.3. A generator comprising a double set of field elements axially displaced, windings on polar projections of said elements, a rotor having outer portions cooperating with said field elements and an intermediate portion, and av Winding embracing said intermediate portion, said first-named windings and said latter windings being connected in circuit with each other.

4. A generator comprising a double. set of field elements axially displaced, each of said elements forming a multipolar field frame, windings on polar projections of said elements, a rotor having outer portions cooperating with said field elements and an intermediate portion, each of said outer portions being of symmetrical form and balanced, and a winding embracing said intermediate portion, said first-named windings and said latter windings being connected in circuit with each other.

5. A generator comprising a double set of stationary laminated field element's axially displaced, stationary portions of magnetic material for conducting the magnetic tlux between said stationary elements, a plurality of windings on said elements and connected together in a circuit, a rotor cooperating with said elements, a generating winding embracing said rotor, said gene 'ating winding being connected in the circuit of said plurality of windings, a second winding subjected to change of magnetic flux through said generating windin and means for making and breaking the circuit of said generating windin 6. A generator comprising a double set of permanently magnetized laminated multipolar stationary field elements axially displaced, stationary portions of magnetic material for conducting the magnetic flux between said stationary elements, a rotor cooperating with said elements having balanced end portions, a generating winding embracing said rotor, at second winding subjected to change of magnetic flux through said generating winding and means for making and breaking the circuit of said generating winding.

TQA generator comprising a double set of field elements axially displaced, a rotor cooperating with said elements, windings on said elements, a generating winding embracing said rotor connected n circuit with said first-named windings, a second winding subjected to change of magnetic flux through said generating winding, and means for making and breaking the circuit of said generating windin 8. A generator comprising a double set of permanently magnetized field elements. axially displaced, a rotor cooperating with said elements, windings on said elements, a generating winding embracing said rotor and connected to said windings, a second winding subjected to change of magnetic flux through said generating winding, and means for closing the circuit of said winding during generation of elcctromotivc force in a direction to increase the magnetization of said magnetized field elements and for keeping the circuit. open during generation 01' elcctromotive force in the opposite dire -t ion.

9. A generator comprising a double set of permanently magnetized laminated multipolar field elements axially displaced. windings on said elements, a rotor cooper ating with said elements having balanced end portions, a generating winding embracing said rotor connected to said windings. a second winding subjected to change of magnetic llux through said generating winding. and means for closing the cll't'llli t said generating winding during generation of electromotive force in one direction and for keeping the circuit open during generation of clectromotire force in the opposite direction.

10. A generator comprising a double set of field elements axially displaced, a rotor cooperating with said elements, windings on said elements. a generating winding embracing said rotor connected in circuit with said first-named windings, a second wind ing subjected to change of magnetic tlux through said generating winding. and means for closing the circuit of said generating winding during generation of electromotive torce. in one direction and for keeping the circuit open during generation of electromotirc force in the opposite direction.

11. A generator comprising a field frame, a winding on said field frame, a rotor, a generating winding embracing said rotor. said windings being connected in circuit with each other. and means for closing the circuit of said windings during generation of electromotire force in one direction and for keeping the circuit open during generation of electromotive force in the opposite direction.

12. A generator comprising a field frame, a winding on said field frame, a main generating winding, said windings being connected in circuit with each other, a secondary winding forming a part of said generator and subjected to change of magnetic flux through said generating winding, and means for closing the circuit ofsaid firstnamed windings during generation of electromotive force in one direction and for keeping the circuit open during generation of electromotive force in the opposite direction.

13. A generator comprising a stationary field frame, a Winding on said frame, a rotor, a stationary winding subjected to change of magnetic flux through said rotor, a secondary stationary winding in mag-' netic relation 'to said second-named Winding, and means for closing the circuit of sald first and second named windings during generation of electromotive force in one direction and for kgep ing the'circuit open during generation 0 electromotive force in the opposite direction.

14. A magneto generator comprising a double set of laminated permanently..mag netized mult-i olar field elements axially displaced, axial y extending portions ofrsoft iron connecting said elements, a rotor cooperating with said elements, a generatin Winding embracing said rotor and a secon winding subjected .to change of magnetic flux through said generating winding.

In testimony whereof afiix my signature, in presence of two witnesses.

LEON J. LE PONTOIS.

Witnesses:

L. K. SAGER, Geo. U. KERR.

00pm ot-thll patent Indy be obtained for five cents each, by addressing the "Commissioner of Patents,

Washington, I). 0. 

